Teachers in the classroom need to be able to modify instruction in a meaningful way that helps students to improve academically. School districts provide electronic assessment data which helps teachers identify areas for improvement within their instruction. Electronic performance assessment systems can be an effective means of assisting schools to improve assessment scores. While teachers often have access to these electronic assessment performance systems, understanding how to use them, and effectively using them in practice can be challenging in many districts. The purpose of this phenomenological qualitative study was to examine how elementary school teachers use an electronic assessment performance system to improve lessons and enhance classroom instruction. The study employed the use of interviews in order to collect information from teachers about how they used electronic assessment performance systems, the benefits they derived, and the challenges of using these systems. Overall, the study found a need for collaborative time where teachers have an opportunity to review and analyze data as teams in order to offer suggestions for enhancing instruction. The researcher provides additional recommendations for various stakeholders as well as future research possibilities. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]